Voltage Reg. or Alt.?

[baff2004]

My X recently has had some trouble idling, and I noticed that the battery gauge fluctuates from normal voltage to low voltage. And when it starts dropping voltage the X has a hard time idiling and will occasionally stall. There is no battery light that comes on or anything, so thats weird, but I was thinking that this was more of a regulator problem then an alt. problem. Any ideas? This this a replaceable part, or do I need a new alt.?

 

[ExplorerDMB]

I'm not sure exactly how the Explorers Alternators are, but most newer model vehicles have the regulators inside the alternator.

-Drew

 

[BrooklynBay]

Since the newer design has an internal regulator, the heat affects the electronics more, and causes a lower voltage than alternators with an external regulator. Some aftermarket kits actually have regulator wiring harnesses with an adapter to bypass the internal regulator. You would have to know if your regulator is a positive regulator, or a negative regulator before you experiment with it by looking at a charging schematic. The output to your rotor is what comes off of the regulator. I actually have both, an internal, and external regulator system on my vehicle. I added the external regulator on my own which helps the internal one out when its voltage starts to drop when it warms up.

 

[baff2004]

Ok, So I replaced the Alt. which has an internal regulator built in, with a rebuilt 130Amp alt. that I bought at Napa. Within 20 mins. it was installed and everything, when the moment of truth came, I turned over my X and it began to do the same thing, and was dropping voltage when it was in park or neutral. Another weird thing was that when the vehicle is in any gear it doesn't tend to drop voltage unless I switch the headlights on or put some sort of load on it. I also have 4 KC Daylighters, that when are switched on, and the X is idiling it idles at very low rpm. I took my X over to PepBoys to get all the electrical components tested, and everthing tested out fine. Has anyone else has this problem? My X never used to do this before...

 

[BrooklynBay]

What electrical things did they test? Was it the battery, battery drain when the vehicle is parked, or a voltage test when you turn on your headlights, and other accessories?

 

[mersberg]

Since the newer design has an internal regulator, the heat affects the electronics more, and causes a lower voltage than alternators with an external regulator. Some aftermarket kits actually have regulator wiring harnesses with an adapter to bypass the internal regulator. You would have to know if your regulator is a positive regulator, or a negative regulator before you experiment with it by looking at a charging schematic. The output to your rotor is what comes off of the regulator. I actually have both, an internal, and external regulator system on my vehicle. I added the external regulator on my own which helps the internal one out when its voltage starts to drop when it warms up.

Brooklyn,
Any info on the regulator bypass, I have a 2000 V6 with a 130 amp that stays below 13.8 volts and sometimes drops lower during idle. Would like to maintain 14.5 volts all the time. Thanks

 

[inh]

http://www.explorerforum.com/forums/showthread.php?p=1722521#post1722521

 

[BrooklynBay]

The external voltage regular that I used on my 1988 van is a 3 prong Chrysler performance regulator. I think it's from Mopar Sport or something like this. I put it in about 15 years ago, so I don't know the part number.

 

[mersberg]

The reason I want to do this is I purchased an Excessive Amperage alternator and I had it repaired by EA and it never lasted long before the same problem. I get 13.8 volts at 1000 or more rpm and about 188 amps with a load at 2000 rpm. It is a 300 amp alternator and it seems to me that the rectifier and regulator is the culprit. I want to avoid going back to EA and repair it myself. HO alternator manufacturers go somewhere for these HO parts, so why can't I just replace the bad parts from the same places. My alt. has a heavier stator so i know its got to be a higher output, so whynot change the rectifier and maybe convert to external regulator.
http://rjminjectiontech.com/?p=7
http://www.wai-wetherill.com/publications/Transpo_Apr-May06.pdf

 

[fixxxer]

I think you should be looking at the idle issue first, if the truck isn't idling at the correct RPM's, the alternator could be turning below the threshold it needs to give you the proper voltage/current.

 

[mersberg]

With the stock alternator I have no issues however I do not have enough amperage for my stuff.

 

[mersberg]

Update
I been researching my EA alternator and found the recitfier he uses is a Transpo FR3003SP which relates to a Hi amp rectifier replacement , I read on their site upwards of 240 amps, utilizes heavy duty avalanche diodes more diodes less heat. I also found a conversion regulator to convert internal regulator to external regulator type , from A-circuit to B-circuit regulator. The reason I wasn't getting above 13.8 volts was the regulator was set to 13.8volts.A option for that is to by the regulator with a higher set point also sold by them. So the regulator I have is doing its job, now its on to why my rectifier isn't doing 200 or more amps. I know the stator is alot heavier then stock and the rectifier is practically new, could my brushes cause this problem? I get 180 amps so its more then stock , its just not as much as 300 amps. If nothing else works I hope I helped someone in more options for there alternator upgrades.All the parts are made bu Transpo and can be bought from Springhillautoelectric.

High output rectifier
http://www.springhillautoelectric.com/index.php?act=viewProd&productId=151

To rebuild alt to higher output
http://cgi.ebay.com/ebaymotors/FORD...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

Conversion int to ext need to also buy external regulator , maybe an
adjustable as an option
http://www.transpo.de/cgi-win/product.exe?F796BNC
http://www.springhillautoelectric.com/index.php?act=viewProd&productId=182

for higher voltage regulation at 14.6
http://www.springhillautoelectric.com/index.php?act=viewProd&productId=158

Transpos catalog
http://www.transpo.de/Catalog/Browse.htm